Intravenous catheter assembly



Novfl 14, 1967 s, H'IRSCH 3,352,306

INTRAVENOUS CATHETER ASSEMBLY Filed Dec. 23, 1963 3 Sheets-Sheet 1INVENTORf 5 SIDNEY HIRSCH ATTORNEY Nov. 14, 1967 s. HIRSCH 3,352,306 IINTRAVENOUS CATHETER ASSEMBLY Filed Dec. 23, 1965 3 Sheets-Sheet 2FIG.||

INVENTOR. SIDNEY HIRSCH ATTORNEY Nov. 14, 1967 s HIRSCH INTRAVENOUSCATHETER ASSEMBLY 3 Sheets-Sheet 3 Filed Dec. 23, 1963 FIG. l5 F|G.l6

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FIG. l9 FIG. 20

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INVENTOR. S l D N E Y H l R S C H, BY fix W A T T O R N E Y UnitedStates Patent 3,352,306 INTRAVENOUS CATHETER ASSEMBLY Sidney Hirsch, 501Broadway, Cedarhurst, N.Y. 10012 Filed Dec. 23, 1963, Ser. No. 332,658 1Claim. (Cl. 128-214.4)

This invention relates in general to a certain new and usefulimprovement in surgical devices and, more particularly, to intravenouscatheters.

The intravenous administration of fluids to a patient has, in recentyears, been accomplished in various ways. One technique, which is beingused with increasing frequency, involves the introduction, into thepatients vein, of a so-called plastic catheter or cannula. Preferably,such device consists of a length of flexible non-toxic tubing made ofpolyethylene, polyvinyl or other suitable synthetic resin. Preferably,though not necessarily, the resin is compounded or pigmented with aradio-opaque material. One method of installing the cannula in thepatients vein is to perform a veni-puncture with a large-bore hypodermicneedle and then thread the cannula through the needle. After the cannulahas been threaded far enough into the vein, the needle is removed. Thistechnique, however, leaves the hypodermic needle attached to theexternal end of the cannula and, in many cases, this is not considereddesirable.

For many routine situations, it is preferable to insert the cannula bythe use of an internal stylet which can be entirely removed after thecannula is in place within the vein. By this technique, it is possibleto use a larger cannula so that infusions, transfusions, and aspirationscan be conducted more rapidly.

However, the doctor or technican can only ascertain when a vein has beenentered by observing the outflow of blood into the cannula andconventional stylets make this permit purging the cannula of entrappedair which might produce an embolism if injected into the vein.

It is, therefore, the primary object of the present invention to providean improved type of combined intravenous catheter and stylet that isuniquely adapted for blood transfusion, intravenous feeding, and otherintravenous, intraarterial or intra-lymphatic therapy.

It is another object of the present invention to provide an intravenouscatheter which may be introduced into the vein by means of an internalstylet which can then be removed entirely from the catheter leaving onlythe flexible non-metallic element within the patients vein.

It is an additional object of the present invention to provide anintravenous catheter which is substantially transparent so that theoutflow of blood therethrough can be readily observed as an indicationthat the catheter has been properly introduced into the patients vein.

It is also an object of the present invention to provide an intravenouscatheter of the type stated in which the outflow of blood can be readilyand efficiently controlled for purposes of purging the catheter toremove entrapped air.

It is a further object of the present invention to provide anintravenous catheter having light-weight transparent external connectionmeans for a flexible tube or conduit through which the administeredfluid can pass.

It is likewise an object of the present invention to provide anintravenous catheter of the type stated which can be allowed to remainin the patients vein for substantially long periods of time withoutimmobilizing the patients arm or otherwise causing discomfort to thepatient.

With the above and other objects in view, by invention resides in thenovel features of form, construction, arrangement, and combination ofparts presently described and pointed out in the claim.

In the accompanying drawings (three sheets)- FIG. 1 is a perspectiveview of an intravenous catheter constructed in accordance with andembodying the present invention;

FIG. 2 is an exploded perspective view of the intravenous catheterillustrating the several component parts thereof;

FIG. 3 is a longitudinal sectional view taken along line 3-3 of FIG. 1;

FIGS. 4 and 4 are fragmentary perspective views of the intravenouscatheter after it has been inserted into the vein and showing the mannerof use thereof for the intravenous administration of fluids to apatient;

FIG. 5 is a transverse sectional view taken along line 55 of FIG. 3;

FIG. 6 is an enlarged fragmentary side elevational view of thecoupling-end of the intravenous catheter;

FIG. 7 is a longitudinal sectional view taken along line 77 of FIG. 6;

FIGS. 8, 9, and 10 are transverse sectional views taken along lines 8-8,99, and 1010, respectively, of FIG. 7;

FIG. 11 is an enlarged fragmentary longitudinal sectional view of thesheath-end of the intravenous catheter;

FIG. 12 is a longitudinal sectional view taken along line 1212 of FIG.11;

FIG. 13 is a side elevational view of a modified form of intravenouscatheter constructed in accordance with and embodying the presentinvention;

FIG. 14 is an enlarged fragmentary perspective view of the stylet-end ofthe intravenous catheter shown in FIG. 13;

FIGS. 15 and 16 are transverse sectional views taken along lines 15-45and 1616, respectively, of FIG. 13;

FIG. 17 is a side elevational view of another modified form ofintravenous catheter constructed in accordance with and embodying thepresent invention;

FIG. 18 is an enlarged fragmentary perspective view of the stylet-end ofthe intravenous catheter shown in FIG. 17; and

FIGS. 19 and 20 are transverse sectional views taken along lines 19-19and 20-20, respectively, of FIG. 17.

Referring now in more detail and by reference characters to thedrawings, which illustrate practical embodiments of the presentinvention, A designates an intravenous catheter which essentiallyconsists of four separable parts, namely, a catheter 1, a stylet 2, asheath 3, and an end plug 4 as shown in FIGS. 1 and 2.

.The catheter 1 comprises an elongated hollow tube or cannula 5 formedof a suitable synthetic resin, such as polyethylene, for example, andbeing adhesively secured at its distal end with a tubular sleeve 6formed integrally on the forward end of a coupling-socket 7, which isflared outwardly and integrally provided at its remote or distal endwith a diametrally enlarged peripheral flange 8. The coupling-socket 7is interiorly formed to provide an inwardly and forwardly taperingrecess 9 which is of substantially larger diametral size than theflexible tube or cannula 5 so as to form an internal chamber 10.Moreover, the coupling-socket 7 is preferably formed of a highlytransparent or translucent synthetic resin, such as methyl methacrylateor the like, so that the interior of the chamber 10 can be visuallyobserved, if desired. Along its forward end, the tube or cannula 5 istapered down as at 11 to provide a somewhat thinner wall tip 12 which isof reduced inside and outside diametral dimension as compared with theinside and outside diametral dimensions, respectively, of the rearwardmain portion of the tube or cannula 5.

The sty1et2 preferably consists of a hollow tubular steel needle ithaving a sharpened bevel end e which is capable of cleanly and easilypenetrating the patients arm in entering the lumen of the vein, arteryor lymph vessel. At its remote or distal end, the needle n is. rigidlyand immovably mounted within a sleeve-portion 13 which is integrallyformed on the forward end of a tubular fitting 14, which is, in turn,integrally provided with a diametrally enlarged peripheral flange 15 anda plurality of axially extending tapering ribs 16. Internally, thefitting 14 is provided with a diametrally enlarged coaxial chamber 17which is counterbored or otherwise suitably formed at its distal end toprovide a tapered recess 18. In this connection, it should also be notedthat the sleeve-portion 13 is externally tapered and is of such axiallength as to fit snugly and firmly within the matching internallytapered coupling-socket 7, substantially as shown in FIG. 7. It willalso be noted by reference to FIGS. 8 and 9 that the peripheral flange'15 of the sleeve 13 is provided with two diametrally opposed notches19, 20, and the peripheral flange S is similarly provided with a flatsegmental surface 21 that can be axially aligned with either of thenotches 19 or 20 so that the catheter 1 and stylet 2 can be suitablyaligned when in assembled position and manually manipulated, as will bepresently more fully discussed. At its opposite or distal end, thefitting 14 is provided with a narrow external annular rim 22 having twodiametrally spaced radial lugs 23 adapted for retentive engagement witha standard Luer fitting, the latter being entirely conventional and,therefore, not shown or described herein. The fitting 14 is preferablymolded or otherwise suitably formed from a structurally strong, rigid,transparent or translucent synthetic resin, such as methyl methacrylateor the like.

The plug 4 is-also preferably molded from a suitable synthetic resin andintegrally includes a forwardly presented externally taperedmale-portion 24 which is externally sized to fit interchangeably withinthe recess 18 of the sleeve 13 or the chamber 10 of the coupling-socket7. In other words, the male-portion 24 of the plug 4 and thesleeve-portion 13 of the fitting 14 are of substantially the sameexternal size and tapered contour. Internally, the plug 4 is providedwith a closed-end axial bore 25 which is substantially of the samediametral size as the bore 17 of the fitting 14 and is more or less inline therewith when the plug 4 is inserted within the fitting 14, asbest seen in FIG, 7.

The sheath 3 is molded as a single integral element, preferably from aninexpensive synthetic resin, such as polyethylene, and integrallyincludes a tubular quill 26 provided at its remote end or distal endwitha somewhat thickened collar-portion 27 which is internally sized andtapered to fit snugly over and around the sleeve-portion 6 of thecoupling-socket 7. Internally, the sheath 3 is a smooth-surfacedcontinuation of the tapered internal surface of the collar-portion 27,but throughout its length it is of substantially larger internaldiametral size than the external diametral size of the tube Moreover,the quill 26 is substantially greater in axial length than the combinedlength of the tube 5 and stylet needle in, so as to extend a substantialdistance axially beyond the projecting sharpened end e of the styletneedle n and protect it from unauthorized contact with external objectswhich might dull or contaminate the sharpened point thereof. Preferably,the forward end of the quill 26 is slightly reduced and .unclosed in theprovision of an opening 28, for convenience in molding. If desired, thisopening 28 may be closed by a small cotton wad or plug which isconventional and, therefore, not shown or described herein in detail. Itwill also be noted, by reference to FIGS. 1 and 3, that the portion ofthe stylet needle r which projects beyond the socket-retained end isslightly longer than the comparable projecting portion of the tube 5, sothat, when the two are in assembled relation, the taper 11 and reducedtip 12 of the tube 5 respectively will be cated a short distancerearwardly from the sharpened or forward end e of the stylet needle n.Moreover, the ex ternal diametral size of the stylet needle 11 issubstarv tially identical with the internal diametral size of the tip 12of the tube or cannula 5, so that the stylet needle n will fit snugly,but nevertheless slidably, therein when the two are in assembledrelation. For the remainder of its length, the inside diameter of thetube or cannula 5 is, of course, very slightly larger than the outsidediametral size of the needle, so that the fit is free and even Veryslightly loose.

The tapered-fit method of interconnection between the coupling-socket 7and fitting 14 combined with the closely proximate arrangement betweenthe peripheral flanges 3 and 15, respectively, and the alignmentthereof, in etfect creates an integral combination between the stylet 2and the catheter 1, so that there is no tendency for axial shiftingmovement therebetween during the process of punctur= ing the flesh andvein of the patient. This effectively pre-- vents any so-called shirringof the tube or cannula 5 with respect to the stylet needle n as the twopass into the flesh. It will, of course, beapparent that if the tube orcannula 5 begins to shirr or wrinkle up along the outside of the styletneedle n, it becomes virtually use= less and cannot be effectivelythreaded into the vein, Even if, by reason of excessive manipulation,the shirred cathee ter were to be straightened out somewhat andprojected into the vein by main force, it would still be an unacceptable surgical procedure for two reasons. In the first place, theexternal surfaces of the tube or cannula 5 would, very likely, becontaminated to some degree by the manual efforts of straightening itout and, what is more important,

the physical strength of the tube ,5 would besomewhat impaired, so thatthere would be a danger that portions of it might break off in the veinand create a dangerous embolus somewhere in the circulatory system ofthe patient. Actually, it has been thought that by merely tapering theleading end of the tube 5 and providing for a snug fit between thestylet needle n and tube 5, this shirring effect can be overcome.However, it is desirable to have the interior surface of the bore of thetube 5 and the exterior surface of the stylet needle n as smooth aspossible and the diametral tolerances sufficiently precise so that thestylet needle n will provide physical support to the tube 5 while at thesame time being reasonably free to slip axially with respect thereto inorder to facilitate quick, easy, and convenient withdrawal of the.stylet needle n after the veni-puncture is made and the tube 5 isinstalled within the patients vein. If there is any tendency for thestylet needle n to bind within the tube 5, then there isa seriouspossibility that the portion of the tube 5 which has been inserted intothe vein along with the sharpened end of the stylet needle n will tendto shirl or break off as the stylet needle n is being withdrawn.Obviously, this can produce serious consequences. If the inserted end ofthe tube 5 is even slightly shirred within the vein, it can besufficiently enlarged in diametral size so as to produce irritation,vein-blockage, and ultimately lacerationor damage to the vein-walls whenthe tube 5,

is finally removed. It has been found, in connection with the presentinvention, that by providing smooth, firm, but nevertheless slidableinterengagement between the tube 5 and the stylet needle n, and, at thesame time, providing firm interengagement between the coupling-socket 7and fitting 14, so that these two elements can be manipulated as avirtually integral unit during the making of the venipuncture, it ispossible to avoid any axial shifting movement between the tube 5 and thestylet, needle n and thereby the danger of shirring is effectivelyobviated both during the making of the veni-puncture and the re-v movalof the stylet needle n.

The interengagement between the coupling-socket 7 and the fitting 14serves an additional unique function. The doctor or technician, inmaking a veni-puncture can only determine that the vein has beenpenetrated by visually observing the outflow of venous blood. As hasbeen above indicated, this type of observation has been difficult, and,in many instances, impossible, with some existing types of flexiblecatheter sets. With the intravenous catheter of the present invention,however, venous blood will immediately flow up through the hollow styletneedle n, as soon as the vein is penetrated, and will appear as a highlyvisible, red column within the chamber 17 of the transparent fitting 14.Any air which is entrapped within the bore of the stylet needle n andthe chamber 17 will be compressed slightly into the chamber 25 of theplug 4 until pressure-equilibrium has been established betweenvenous-pressure and the back-pressure created by the degree ofcompression of the air into the chamber 25 of the plug 4. Obviously,there will be no loss of blood and the amount of blood which actuallyflows out through the stylet needle 11 and into the chamber 17 of thefitting 14 will be minimal. However, this outflow of blood will occurimmediately upon penetration of the vein so that the doctor ortechnician will know that the veni-puncture has been fully andefiectively completed and that further insertion of the sharpened end eof the stylet needle n can be avoided. By this means, it is possible toavoid pushing the sharpened end e of the stylet needle n all the wayacross and through the opposite side of the vein.

As soon as the patients vein has been entered, as indicated by thevisible outflow of venous blood which will appear in the fitting 14, thedoctor or technician can immediately suspend manipulation of thecatheter-set A and gently rotate the fitting 14 with respect to thecouplingsocket 7, thereby disengaging the former from the latter so thatthe stylet needle n can be withdrawn axially from the catheter 1 and, atthe same time, the tube 5 thereof can be pushed forwardly into the veinindependently of the stylet needel it. When the sharpened or tip end eof the stylet needle n has been withdrawn until it is approximatelymidway or three-fourths of the distance out of the catheter 1, thedoctor or technician can place a thumb or finger upon the forward freeportion of the tube or cannula 5 and compress it sufliciently to stopthe outflow of venous blood, whereupon the fitting 14 with itsassociated stylet needle n can be entirely withdrawn from thecoupling-socket 7 and associated catheter 1. Thereupon, the plug 4 canbe removed from the fitting 14 and inserted into the coupling-socket 7so as to act as a closure therefore. During this latter operation, theair which is entrapped within the recess or bore 25 of the plug 4 willreturn to atmospheric pressure, so that, when the digital pressure whichhas been applied to the catheter 1 is relieved, venous pressure willproduce an outflow of blood through the tube 5 into the chamber 9 of thecoupling-socket 7, substantially filling it and establishing apressure-equilibrium of the type previously mentioned. The catheter 1can then be bound firmly down against the patients arm by a strip ofadhesive tape 1 substantially as shown in FIG. 4.

Whenever it is desired to administer an intravenous feeding, carry out ablood transfusion, or administer any other fluid intravenously, it ismerely necessary to place a piece of sterile gauze on the patients armbeneath the plug 4 and coupling-socket 7. The exposed portion of thecatheter 1 can then be manually squeezed to control the flow of venousblood, whereupon the plug 4 can be removed and the chamber 10 of thecoupling-socket 7 can be allowed to fill up with blood. It has beenfound that this can be controlled rather precisely by reason of thetransparent nature of the coupling-socket 7, but, at the very most, onlyone or two drops of blood need be lost on the piece of gauze. In anyevent, it is desirable to avoid the entrapment of any air bubbles in thechamber 10 of the coupling-socket 7. A conventional tapered fitting f,which is connected by a suitable supply-hose h, is then manuallyinserted into the coupling-socket 7, substantially as shown in FIG. 5,and the intravenous administration will proceed in the usual manner.Whenever sufficient fluid has been administered to the patient, the tube5 can again be manually squeezed shut and the fitting 1 replaced withthe plug 4.

It is also possible to provide a modified form of intravenous catheterset A, which includes a catheter 1 and plug 4', substantially identicalwith the previously described catheter 1 and plug 4. Provided forcooperation with the catheter 1 and plug 4' is a stylet 29 whichincludes a fitting 14' substantially identical in all respects with thepreviously described fitting 14. Rigidly mounted in the fitting 14 is asolid rod-like stylet needle n having a forwardly projected sharpened orpointed end 30 and an axially extending flat surface 31 which extendsall the way through the interior of the catheter 1' and terminateswithin the interior of the coupling-socket 7'. In this particularembodiment, there is no communication through the stylet needle n to theinterior of the fitting 14. Consequently, as soon as the vein has beenpenetrated, venous blood will flow up along the flat surface 31 and willbe visible as a thin red axial line along the catheter 1. This outflowof venous blood may partially fill the chamber within thecoupling-socket 7. As soon as the vein has been properly entered, thecatheter 1' can be pushed forward into the vein and the stylet 29withdrawn, substantially in the same manner as above set forth inconnection with the previously described catheter set A.

It is also possible to provide a modified form of intravenous catheterset A", which includes a catheter 1" and plug 4", substantiallyidentical with the previously described catheter 1 and plug 4. Providedfor cooperation with the catheter 1" and plug 4" is a stylet 32 whichincludes a fitting 14" substantially identical in all respects with thepreviously described fitting 14. Rigidly mounted in the fitting 14" is asolid rod-like stylet needle n" having a forwardly projected sharpenedor pointed end 33 and an axial kerf or slot 34 which extends all the waythrough the interior of the catheter 1" and terminates Within theinterior of the coupling-socket 7". In this particular embodiment, thereis no communication through the stylet needle 11" to the interior of thefitting 14". Consequently, as soon as the vein has been penetrated,venous blood will flow up along the axial kerf or slot 34 and will bevisible as a thin red axial line along the catheter 1". This outflow ofvenous blood may partially fill the chamber within the coupling-socket7". As soon as the vein has been properly entered, the catheter 1" canbe pushed forward into the vein and the stylet 32 withdrawn,substantially in the same manner as above set forth in connection withthe previously described catheter set A.

It should be understood that changes and modifications in the form,construction, arrangement, and combination of the several parts of theintravenous catheters may be made and substituted for those herein shownand described without departing from the nature and principle of myinvention.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

In an intravenous catheter assembly comprising a stylet of uniform crosssectional configuration throughout its length provided at one end with asharp point capable of penetrating the flesh and puncturing a vein, saidstylet rigidly terminating at its other end in a handle-forming element,a coupling-socket removably seated upon one end of said element in sucha manner that it can be manually removed from the handle-forming elementbut when so seated will be firmly joined with said element whereby tomove unitarily in all directions withsaid element, and a flexiblecatheter-tube rigidly integral at one end with the coupling socket andextending outwardly therefrom in telescopic disposition around thestylet and terminating a short distance inwardly from the sharp point ofthe stylet so that when the coupling socket is in seated position thesharp point will protrude outwardly from the catheter tube a generallyannular substantial length of the catheter tube at the distal endthereof forming a tip portion having inside and outside transversedimensions respectively less than the inside and outside transversedimension of the remainder of the catheter tube, and a wall thicknessless thanthe wall thickness of the remainder of the catheter tube whichremainder comparatively loosely surrounds the stylet, the insidediameter of the tip portion being substane tially the same as theoutside diameter of the stylet so that the tip portion of the cathetertube snugly engages the adjacent portion of the stylet whereby the tipportions of the catheter tubeiand stylet can unitarily be pushed axiallythrough the flesh and into a lumen without shirrin'g, fragmentingwrinkling and the like at the tip portion of the catheter tube.

' References Cited UNITED STATES PATENTS 2,836,180 5/1958 Strauss128-216 8 3,030,953 4/1962 Koehn 128214 3,094,122 6/1963 Gauthier et a1128221 3,097,646 7/1963 Scislowiczv 128-214 3,204,634 9/1965 Koehn128-214 FOREIGN PATENTS 716,726 10/1931 France. 1,092,011 11/1954France.

OTHER REFERENCES Eisenberg: A Modified Instrument for Thoracentesis,Paracentesis, and Intravenous Fluid. Therapy. New Enlland Med. Jour.,Jan. 17, 1963, pp. 143-144.

15 DALTON L. TRULUCK, Primary Examiner.

ROBERT MORGAN, Examiner.

